<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        *{
            padding: 0;
            margin: 0;
        }
        .c1{
            height: 500px;
            background-color: black;
        }
         .c2{
            height: 500px;
             background-color: blue;
        }
         .box{
             width: 160px;
             height: 210px;
             background-color: white;
             position: fixed;
             bottom: 180px;     /*距离下面的距离*/
             left: -80px;
         }

         .box:hover{   /*鼠标选中事件*/
             left: 0;
         }
         .box .box1{
             margin: 8px;
             border: 2px solid #FFEDF1;
             padding: 20px 15px 8px;
         }
         .box .box1 img{
             width: 100%;
             height: 100%;
             display: block;
         }
         .box .box1 .box2{
            color: #666666;
             margin-top: 10px;
             font-size: 14px;
             text-align: center;
         }
    </style>
</head>
<body>
    <div class="c1"></div>
    <div class="c2"></div>
    <div class="box">
        <div class="box1">
            <img src="二维码.png">
            <div class="box2">
                <div>微信扫码下载</div>
                <div>App专享优惠</div>
            </div>
        </div>
    </div>
</body>
</html>